class Animal(object):
    def eat(self):
        print("eating...")

    def sleep(self):
        # print("self...", id(self))
        print("sleeping...")

class Dog(Animal):
    def swimming(self):
        print("swimming...")

    def sleep(self):
        # Animal.sleep(self)
        super().sleep()
        print("侧翻睡")

dog = Dog()
dog.sleep()